1. Field of the Invention
This invention relates to an escalator, and more particularly to a dual-purpose escalator for wheelchairs which is capable of transporting wheelchairs for physically handicapped persons as well as ordinary users.
2. Description of the Related Art
Usually, the general escalators cannot safely transport wheelchairs for physically handicapped persons in the horizontal attitude because the depth dimensions of the steps are short. For this reason, recently, escalator systems have been considered in which specialized steps are included in part of the endlessly arranged multiple steps. These are expanded by mechanically altering their configuration when in the wheelchair loading operation mode. Thus, a deeper space for wheelchair loading can be ensured.
An escalator compatible with wheelchairs is described using FIGS. 15 to 20. In FIG. 15, 1 is a main-frame (generally called a "truss") positioned at a slope between a landing 2 and a landing 3 on lower and upper floors. 4 is a wheelchair in which a physically handicapped person is seated and 5 is an attendant. 6 is an attendant call button provided close to landing 2. 7 are shift switches for the wheelchair loading operation mode provided in balustrade 1a of the escalator. 8 are also wheelchair operation buttons.
In FIG. 15, 9 are the multiple steps which are arranged and run in an endless form on a path constructed in main-frame 1 using guiderails and the like. The design is that the treads of several steps 9 become of the same height as each other on the horizontal path sections at the lower and upper floors, and that the treads of each step 9 form stairs with levels differing from each other to run in the sloping section between.
Here, in multiple steps 9, 10 is a first specialized step, 11 is a second specialized step and 12 is a third specialized step. These steps are used for wheelchair loading. 13 is an activating apparatus which causes specialized steps 10, 11 and 12 to alter their configurations to a first state in which a wheelchair can be loaded when in the wheelchair operation mode, or to be restored to a second state for the normal operation mode.
When these first, second and third specialized steps 10, 11 and 12 become in the wheelchair operation mode through shift switch 7, the design is that first specialized step 10 is firstly activated by activating apparatus 13 and part of step 9 is caused to tilt. Then, second specialized step 11 is activated by activating apparatus 13, and a linking system 22 provided inside it is engaged with third specialized step 12. Third specialized step 12, which is linked by linking system 22, is supported by second specialized step 11 on the inclined part of the escalator, so that a level space for loading wheelchairs of just 2 steps is ensured.
Specialized steps 10, 11 and 12 and activating apparatus 13 are further described using FIGS. 16 to 20. First, activating apparatus 13 is provided on main-frame 1 which is the running path for steps 9 to 12, and has rack 13b as an engagement member capable of up and down movement through elevator mechanism 13a.
Also, first to third specialized steps 10, 11 and 12 are provided with pinions 14a, 14b and 14c, respectively, which are toothed rotors for operating power input which rotate by engaging with rack 13b and are mounted on each of their inner lower sides. At the same time, they are provided with drivers 15a, 15b and 15c which drive mechanisms inside the steps linked with pinions 14a, 14b and 14c, respectively. During normal operation mode, these pinions 14a, 14b and 14c do not engage with rack 13b, which is withdrawn to the lower position of activating apparatus 13 as shown in FIG. 16. During the wheelchair loading operation mode, the pinions 14a, 14b and 14c rotate by engaging with rack 13b, which is raised by elevator mechanism 13a of activating apparatus 13 as shown in FIG. 17, while running in the horizontal path sections at the lower or upper floor. Thus, drivers 15a, 15b and 15c are operated in linked motion with pinions 14a, 14b and 14c, respectively.
First, specialized step 10 is provided with a tilting step section 16 capable of tilting partically and a surrounding fixed step section 17. As shown in FIG. 16, in the normal operation mode, a bolt 18a projects from driver 15a mounted on tilting step section 16 and engages with a retainer 19a of fixed step section 17. Thus, tilting step section 16 and fixed step section 17 are incorporated as one horizontal surface. In the wheelchair loading operation mode, drive 15a withdraws bolt 18a by the rotation of pinion 14a which engages with rack 13b of activating apparatus 13 as described above, and disengages it from retainer 19a as shown in FIG. 17. And when running on the sloping section, tilting step section 16 changes its configuration to a tilted state about a tilting rotation shaft 20, as shown in FIG. 18.
Second specialized step 11 is provided with linking system 22 so that it links with and supports the tread of third specialized step 12 to form a deep tread of 2 step's depth when running on the sloping section.
This linking system 22 links with and supports, or releases the link with, a movable step section 23 of third specialized step 12 by thrusting forward or withdrawing a rack-toothed coupling rod (fork) 22a in linked motion via a gear 21 with the forward or reverse rotation of driver 15b.
Third specialized step 12 is provided with a movable step section 23 which is supported by linking system 22 of second specialized step 11, and a fixed step section 24 which guides and supports movable step section 23 so as to rise and fall via link 25 of a pantagraph. In the normal operation mode, as shown in FIG. 16, a bolt 18c is projected by driver 15c mounted on fixed step section 24 and is engaged with a retainer 19c of movable step section 23. Thus, movable step section 23 and fixed step section 24 are incorporated as one. When in the wheelchair loading operation mode, as shown in FIG. 17, driver 15c withdraws bolt 18c and disengages it from retainer 19c by the rotation of pinion 14c which engages rack 13b of activating apparatus 13. At the same time, movable step section 23 is linked with and supported by coupling rod (fork) 22a of linking system 22 which thrusts forward from second specialized step 11. The design is as shown in FIG. 18, movable step section 23 follows, even on the sloping section, at the same height as that of second specialized step 11 by means of the upward movement of link 25.
Also, wheel-stops 36 are provided in third specialized step 12 to prevent the falling of a wheelchair during the loading of wheel-chair 4. These wheel-stops 36 are projected from and retracted into the tread by driver 15c.
FIGS. 19 and 20 are drawings showing external appearances of first to third specialized steps 10, 11 and 12. FIG. 19 shows the running state on the sloping section in the normal operation mode, and FIG. 20 shows the running state on the sloping section in the wheelchair loading operation mode.
However, escalator constructed in the above, when shifting from the normal operation mode to the wheelchair loading operation mode, as shown in FIG. 17, elevator mechanism 13a of activating apparatus 13 operates and raises rack 13b, which is the engagement member, while running (in the horizontal path sections at the lower and upper floors). Pinions 14a, 14b and 14c, which are the toothed rotors for inputting the operating forces for first to third specialized steps 10, 11 and 12 which come running in succession, successively engage with rack 13b and rotate. Specialized steps 10, 11 and 12 operate through drivers 15a, 15b and 15c which are linked to the pinions 14a, 14b and 14c, respectively, and change their configuration to enable wheelchair loading. However, at this time, when each pinion 14a, 14b and 14c starts to engage with rack 13b, the tips of the teeth will mutually interfere and excessive force will be generated if the phases of the two gears are not matched. When moving to the correctly engaged state by the pinion tooth tips sliding over the rack teeth, a shock will occur with a loud noise. This has an adverse effect on the protection of the mechanism and causes insecure feelings in the operators and the wheelchair users.
However, in the prior art dual-purpose escalator for wheelchairs as described above, when the specialized step configuration was being changed or the linking system did not operate, the design was to stop the escalator by operating a safety system. However, it was difficult to judge from the external appearance how the failure had occurred in each respective specialized step. Therefore, it was necessary to carry out an inspection by entering inside trues 1 of the escalator. This gave rise to problems of poor workability and accompanying danger.
The problem in the step construction mentioned above, which is the focal point of this invention, is the wheel-stop mechanism provided in the third specialized step.
As wheel-stop mechanisms proposed in prior art, there are Japanese Patent Publication No. Showa 63-17438 and Japanese Patent Publication No. Showa 63-51956.
Although not illustrated, these are both wheel-stops which are mechanically projected. In their methods the wheel-stops are projected to specified heights or retracted to their original positions when driving forces are applied by wheel-stop mechanisms.
However, these types of wheel-stop mechanisms have the following problems. That is to say, the case of a wheelchair or the like loaded directly above the wheel-stop mechanism for some reason or other can be considered. In such a case, with the wheel-stop mechanisms mentioned above, the following states may happen. That is, the wheel-stops may push the wheelchair upwards, or they may become in an overloaded state in which they cannot move because of the weight of the wheelchair, or the wheel-stop mechanism may be damaged. None of these states is acceptable.